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Why Do Male Dogs Have Nipples? The Surprising Answer!

By Jacquelyn Kennedy
Updated on

Have you ever noticed that your male dog has nipples and wondered why they are there? The answer to this question may surprise you!

The presence of nipples in male dogs, as well as in male humans, is a result of evolution. But the exact reason behind this phenomenon is not entirely clear.

In this article, we will dive into the science behind why male dogs have nipples and what it can tell us about evolution and biology.

So sit back, relax, and be prepared to have your mind blown by the fascinating world of animal anatomy.

In the Womb…

Let’s go back in time, shall we? Let’s go all the way back to when your pup was in his mother’s womb.

Did you know that all dog embryos are androgynous?

What does that mean exactly….We’ll have to talk science, are you ready?

This means that regardless of what gender they will eventually be, all embryos are initially of indeterminate gender and, so, they initially have characteristics of both male and female genders!

So what does this have to do with your dog having nipples? Let me explain.

Nipples develop in the early stages of a dog’s pregnancy, even before gender is determined! Once the gender is chosen, only then do the reproductive organs begin to develop.

This means that the nipples have already developed even before the gender of the dog is determined!

Read on to know more about the why part…

Okay, I Got The How Part, But Why Do Male Dogs Have Nipples?

For that, you need to ask yourself why do human males have nipples. They don’t serve any purpose and are redundant!

The thing is that your furry friend has nipples just because they were never selected against. What does this mean…?

Do you remember Darwin’s Theory of Evolution by Natural Selection? Here’s what Wikipedia has to say about Natural Selection:

“Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in heritable traits of a population over time.”

This means that since this trait doesn’t have an evolutionary advantage for males, it doesn’t have an evolutionary disadvantage either. And that’s why male dogs have nipples.

Another is that they double up as sweat glands.

Here’s what Dr. Justin A Lee said in his book ‘It’s a Dog’s Life…But it’s Your Carpet : Everything You Wanted to Know About Your Four-Legged Friend’ :

“Mammary glands are basically modified sweat glands that develop from the germinal epithelium. Sounds sexy, no? While humans only develop one pair, dogs typically have five to six….The male nipples are just vestigial, though, and without female hormones, they are non-functioning and lack the “secretory” ability to release or produce milk.”

So this means that even though your male dog may have nipples, they are pretty useless and remain in a rudimentary state.

Now that you know why male dogs have nipples, the next thing you should know is if you need to be worried!

The thing is that nipples help you pinpoint some problems and diseases, but more on that later…

Let’s Find Out More About Your Dog’s Nipples!

No, now that you know that it’s completely normal for your dog to have nipples, let’s know more about them, shall we?

Okay, so let’s study Dog Nipple 101! I’m sure there’s a thing or two you never knew about dog nipples!

Where exactly are your dog’s nipples?

Now that you’ve newly discovered that your male pooch has nipples, are you having trouble locating your dog’s nipples?

Let me help you with that…

Nipples in dogs start from the chest area and go all the way back to the area near the legs.

A dog may have 5-8 pairs of nipples, but it all depends on the breed. In smaller dogs, the average is 8 pairs, and in larger dogs, it is 10!

Yes, I’m not kidding!

Also, each pair of your dog’s nipples have a special name.

Do male dogs have nipples

There are, in fact, names for your dog’s nipples! Let’s go over them, shall we? For reference sake:

  • Cranial thoracic nipples
    • These are the first two nipples on your dog’s chest area.
  • Caudal thoracic nipples
    • These follow the cranial thoracic nipples.
  • Cranial abdominal nipples
    • They are closer to the abdomen and follow the caudal thoracic nipples.
  • Caudal abdominal nipples
    • They are the next in line at the abdomen.
  • Inguinal nipples
    • These are closer to the legs of your dog and the last pair of nipples your dog has!

Do I Need To Worry If My Male Dog Has Nipples?

It is totally normal if your male dog has nipples, but there are a few things that you must look out for:

1. Bacterial Infections

Do male dogs have nipples 1
  • Dogs are prone to getting bacterial infections called mastitis which can happen if your dog’s nipples are scraped.
  • Your dog is more likely to get the infection if it’s short, like a hot dog.
  • What happens in Mastitis?
    • Well, when the bacteria enters the dog’s nipple, they get swollen, have discharge, and are hot and painful for your furry friend.
    • More about it here.

So look out for them!

2. Nipples Can Change Color!

  • Your dog’s nipples do change color as they age, but this isn’t something you need to have a full-fledged panic attack over!
  • Nipples changing color is usually a sign that your dog is getting older and growing darker as they age.
  • But do keep a lookout for any dramatic changes in the coloring.

3. Secretion of Liquid

  • Your male dog’s nipples are in a ‘deactivated’ state.
  • If there’s any liquid discharge, take it as a red flag and go to a vet ASAP and get your doggy friend checked out.
  • The discharge could be a sign of an infection or disease, so don’t take it lightly at all!

4. Enlargement of Nipples

  • This is the most alarming change in your dog’s nipples, and you should not avoid it at any cost!
  • If you see enlarged nipples in your dog, keep an eye out for the following as well:
    • Pain in the abdominal area
    • Anemia
    • Symmetrical hair loss
    • Attracting other male dogs

If you see any of these signs, call your vet and schedule an appointment immediately!

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So What Does This Mean?

To sum it all up…

Yes, your ‘good boy,’ like all mammals, does have nipples! It could range from 6-12 pairs depending on his breed!

The answer to the question, ‘Why do male dogs have nipples?’ isn’t straightforward! It all comes down to evolution, but we can’t really be sure why male dogs (humans, for that matter!) have nipples.

I hope I have helped you find out the answer to your question! If you have more questions, feel free to contact us on our social media pages!

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About the author

Jacquelyn Kennedy

PetDT was founded by Jacquelyn Kennedy, a dog lover and pet admirer. She built the website to provide pet owners with information, experiences, and opinions on breeds, temperament, personalities, health, nutrition, products, and care.

4 thoughts on “Why Do Male Dogs Have Nipples? The Surprising Answer!”

  1. Such a comprehensive post!
    Enjoying your writing style. You help in answering my question. Thank you.

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